The invention relates to a combination apparatus which comprises a video-recorder section and a television-receiver section in a common housing, the video-recorder section comprising at least one rotationally drivable recording and reproducing video signals on/from a magnetic tape which is drivable in its longitudinal direction in adjacent tracks which are inclined relative to the longitudinal direction of the magnetic tape, and the video-recorder section being adapted to reproduce recorded video signals with at least one reproduction tape speed which differs from a recording tape speed, and the video-recorder section comprising a pulse generation device which generates artificial vertical synchronization pulses during reproduction of recorded video signals with a reproduction tape speed which differs from the recording tape speed, and the television-receiver section comprising a picture display device, for displaying video signals reproduced by means of the video-recorder section, and a vertical deflection signal generation device, which generates vertical deflection signals for controlling the vertical deflection in the picture display device and which during the display of video signals reproduced with a reproduction tape speed which differs from the recording tape speed is triggered by artificial vertical synchronization pulses then applied.
Such a combination apparatus of the type defined in the opening paragraph manufactured by the Applicant has, for example, been marketed under the type designation 14TVCR240. In this known combination apparatus the electrical construction of both the video-recorder section and the television-receiver section is as is known per se from apparatuses mounted in separate housings, i.e. from a separate video recorder and from a separate television receiver. In accordance with this construction which is known per se from separate apparatuses the artificial vertical synchronization pulse generated by the pulse generation device of the known combination apparatus and briefly referred to hereinafter as the V-pulse is also applied to an insertion device, by means of which the artificial V-pulses are inserted into the video signals reproduced in a mode referred to as multi-speed reproduction with a reproduction tape speed which differs from the recording tape speed. The composite signal obtained by insertion of the artificial V-pulses into the video signals reproduced in a multi-speed reproduction mode is transferred from the video-recorder section to the television-receiver section, after which the artificial V-pulses are extracted from this composite signal in the television-receiver section and are applied to the vertical deflection signal generation device to trigger this generation device. It is to be noted that the insertion of the artificial V-pulses into the video signals reproduced in a multi-speed reproduction mode with a reproduction tape speed which differs from the recording tape speed is effected because during such a multi-speed reproduction mode the situation may arise that a reproduction error zone, which as is known occurs during such a multi-speed reproduction and which is reproduced as a "noise bar" by a picture display device, appears exactly in the time interval in which the reproduction of a recorded natural V-pulse occurs, in which case the natural V-pulse is not reproduced, as a result of which the vertical synchronization in the picture display device is then disturbed or drops out completely.
In the known combination apparatus a correct vertical synchronization in the picture display device of the television-receiver section and, as a consequence, a steady picture reproduction are not always guaranteed in all the possible multi-speed reproduction modes in spite of the insertion of the artificial V-pulses into the video signals reproduced in a multi-speed reproduction mode with a reproduction tape speed which differs from the recording tape speed. This is because the situation may occur that a reproduction error zone in a reproduced video signal, which zone causes a "noise bar", is situated for example briefly before an artificial V-pulse inserted into the reproduced video signal and that the signal occurring during such a reproduction error zone contains signal components which fake a V-pulse, which signal components are then erroneously recognized as artificial V-pulses in the vertical deflection signal generation device and give rise to a disturbed vertical synchronization in the picture display device and, consequently, in vertical jumping of the displayed picture. Since in the video-recorder section the artificial V-pulses are inserted into the video signals reproduced in a multi-speed reproduction mode and in the television-receiver section they should subsequently be extracted from the composite signal obtained after insertion, false information about the presence of a V-pulse may be derived from the composite signal in the extraction device, which gives rise to an adverse effect in the television-receiver section.